1. Field of the Invention
The invention relates to a power supply technology, and particularly relates to an apparatus for power supply under a power supply framework having a main power circuit and an auxiliary power circuit and a method for power supply thereof.
2. Description of Related Art
When electronic apparatuses are more and more commonly used, the power consumption thereof also increases accordingly. To reduce the power consumption of electronic apparatuses and provide effective power management, a power management mechanism referred to as the advanced configuration and power interface (ACPI) standard has been used to manage the power of electronic apparatuses, and a state of the whole electronic apparatus is divided into six states (S0 to S5) with different power consumption rates according to the power management mechanism based on the ACPI standard.
For the electronic apparatus using the power management mechanism based on ACPI, the corresponding power supply apparatus thereof supports a power supply framework with a main power circuit (+12V, +5V, +3.3V, −12V, −5V) and an auxiliary power circuit (5 Vsb or 12 Vsb). Under such framework, when an external alternating current (AC) power (i.e. the supply mains) is supplied/input to the power supply apparatus, the power supply apparatus continuously generates and outputs an auxiliary power whether it is in an operation state or in a standby state, so as to supply the auxiliary power to a part of loads (e.g. circuits/elements of a power management controller) in the electronic apparatus requiring continuous operation.
However, due to the circuit specification and design concerning the type of typology, the power conversion efficiency of the conventional auxiliary power circuit is lower than the power conversion efficiency of the main power circuit. Thus, the power supply apparatus may generate too much blind power and thus have a less preferable energy saving performance.